Modeling C and N flows through a stream food web: an inverse approach*

Stream Nutrient Concentrations on the Windward Coast of Hawai‘i Island and Their Relationship to Watershed Characteristics

“…In addition, there is no evidence that anthropogenic activities were affecting organic nutrients at the time of the study. The tendency for organic nutrients to become more concentrated with increasing watershed area is consistent with results of a prior study that examined biological in-stream processing in an East Hawai'i stream (Larned et al 2008). …”

“…According to the latest assessment report, the state had 93 streams and 209 coastal water bodies on its §303(d) list of impaired water bodies (State of Hawai'i 2006 (Oki andB rasher 2003, Anthony et al 2004). Other researchers have measured nutrients and/or sediment as part of investigations into anthropogenic effects on stream ecology (Larned and Santos 2000, Laws and Roth 2004, Larned et al 2008, Wiegner et al 2009), terrestrial effects on coastal waters (Soicher and Peterson 1997, Ringuet and Mackenzie 2005, Cox et al 2006, De Carlo et al 2007, and general hydrology Ferentinos 2003, De Carlo et al 2004). Recent measurements of nutrient concentrations and fluxes in O'ahu urban stormwater (Presley and Jamison 2009) provide information relevant to assessing urban impacts on streams.…”

“…A community group attempted to fill in the data gap for streams by monitoring several streams and springs near Hilo ( Young and Godzsak 2008), but their funding was short-lived. Also, there were two recent ecology studies in East Hawai'i that measured organic nutrient fluxes in two streams for several months to 2 yr (Larned et al 2008, Wiegner et al 2009). Those studies notwithstanding, the existing data are insufficient to precisely characterize the concentrations and fluxes of nutrients and sediment in East Hawai'i streams.…”

Differences in ecological structure, function, and native species abundance between native and invaded Hawaiian streams

“…While C. analis are net spinning caddisflies whose diet is largely composed (;90%) of detritus Voshell 1983, Sanchez andHendricks 1997), the gut contents of exotic C. analis from a Moloka'i stream contained nearly 50% of diatoms and algae (Kondratieff et al 1997). Stable isotopes have also demonstrated that algae is an important food source for C. analis (Larned et al 2008, Atwood et al 2010. This suggests that, on Hawai'i, C. analis may be grazing off of substrate surfaces more than their nets (Kondratieff et al 1997) or that algae are growing on C. analis nets.…”